This invention relates to plows, and more particularly to two-way gang plows of the type that is supported on front and rear wheels and towed by a tractor.
The only known two-way gang plows of this type are those disclosed in U.S. Pat. Nos. 3,174,556 and 3,196,955. However, neither of these provides steering of the wheels and neither provides adjustment of lateral spacing between the land sides of adjacent plows to accommodate plowing of various types and conditions of soil. For example, with conventional gang plows of the prior art, plowing of compacted or otherwise dense soils requires either the removal of one or more plow bottoms or the use of a more powerful tractor.
Many two-way plows of the prior art provide diverse mechanisms for controlling a steering tail wheel automatically with steering movement of the tractor which supports the front end of the plow. Some, for example, U.S. Pat. No. 3,511,317 utilizes hydraulic cylinders for the purpose, but none employs master and slave hydraulic cylinders in the manner of this invention. Nor does any such prior art plow enable adjustment of the spacing between the land sides of adjacent plow bottoms automatically with steering adjustment of the tail wheel.
The two-way gang plows of the prior art provide various mechanisms for rolling the plow assembly between right and left hand operating positions. Examples of such mechanisms are disclosed in the patents referred to hereinbefore as well as in U.S. Pat. Nos. 3,524,509 and 3,544,294 and German Pat. No. 2,040,583. However, none of them employs the gearing assembly of this invention. Nor does any such prior art plow provide for automatic readjustment of the angular positions of a front wheel axle and tail wheel relative to a plow frame as the plow assembly is changed between right and left and operating positions.